We have 4 Ryzen PCs in the house including R5-1600X -- the old version of your current 2600. They all play games very well -- and do everything else. Based on our 1600X gaming performance, your 2600 is plenty.
Heck, as a place holder in a PC I built just yesterday, I used a Ryzen 3-1200 4c/4t (the weakest one they make and out of date -- I use it for testing). Tried the R3-1200 in the Assassin's Creed Odyssey benchmark (all Ultra settings, 115% FOV) at 1440p (2K) with RX580 GPU (that I bought for ~$170). Gave low but playable FPS. Not recommending that Ryzen to anyone for anything other than Office PC or HTPC though.
Good to keep it cheap now as the new wave of 7nm CPUs and GPUs hits this summer. That will virtually (not literally) obsolete the current stuff. Next Black Friday may turn out to be a good time to buy (or not, we'll see).
Will be nice to read your opinion on how the build turned out.
RX5700XT 50th Anniversary - 3 monitors = 24P (1200p) + 43"L (2160p) + 24P (1200p), AMD Ryzen 7 3800X, 32GB @3.2GHz, Gigabyte X570 AORUS Pro WIFI MB, (2x M.2 SSD on MB + SSD + 5x HD) = 25TB storage, Rosewill 1050W PSU, Rosewill Thor V2 Case, ASUS AC86U router, VKB Gladiator WW2 Stick, Pedals, Ripjaws KM780 RGB KB, AORUS Thunder M7 Mouse, W10 Pro